Isomerization of wax over catalyst comprising a Group VIII metal, usually platinum support on a fluorided alumina base which has long been practiced.
U.S. Pat. No. 2,668,866 teaches the isomerization of wax using a supported platinum catalyst. The support is preferably an alkali free alumina which has been treated with HCl or HF prior to the incorporates of the platinum.
U.S. Pat. No. 3,308,052 also teaches wax isomerization involving the maximization of jet fuel by careful control of the level of conversion. The catalyst used is a halogen promoted platinum type catalyst.
U.S. Pat. No. 3,365,390 teaches the production of lubricating oil by hydrocracking a heavy oil feed, separating hydrocracked wax from the hydrocracked lube oil portion, and hydroisomerizing the hydrocracked wax using an active reforming catalyst. Active reforming catalysts include platinum-alumina reforming catalyst containing from 0 to 1 wt % halide. Catalysts containing upwards of 2 wt % halide are too acidic.
U.S. Pat. Nos. 4,906,601 and 4,923,588 teach a small particle size low fluorine content catalyst and the use of said catalyst for the isomerization of wax into lube oil base stocks or blending stocks. The catalyst comprises a noble Group VIII metal on fluorided alumina wherein the fluoride content is less than 2 wt % and the support has a particle diameter of less than 1/16 inch. In U.S. Pat. No.4,923,588 eight catalysts are described by example. Pore volumes and surface areas are not recited.
GB 1,499,570 teaches a method for improved white mineral oil production. A catalyst is described for use in the second step comprising a support, palladium and a halogen. The support is a refractory metal oxide such as alumina having a surface area of 25 to 600 m.sup.2 /gram. The alumina support when formed into pellets has an apparent bulk density of from 0.60 gm/cc to 0.85 gm/cc, pore volumes of from 0.45 ml.g to 0.70 ml/gm and surface areas of from 50 m.sup.2 /g to 500 m.sup.2 /gm. In the Example an alumina support extrudate having a surface area of 194 m.sup.2 /gm and a total pore volume of 0.60 cc/gram was used to produce a palladium on chlorided alumina catalyst. This catalyst was used to treat the 650.degree. to 900.degree. F. cut of oil obtained from the first stage hydrogenation zone of the process.
U.S. Pat. No. 2,838,444 teaches an improved reforming catalyst comprising platinum or alumina. An acidic promoter such as fluorine can be added to enhance hydrocracking activity. The isomerization of normal paraffins to isoparaffins is defined in the patent as a reforming operation. The alumina is described as having a pore volume distribution or determined by nitrogen adsorption in the range of 0.1 to about 0.5, preferably 0.15 to 0.3 cc/gram of their pore volume in pores greater than about 100 .ANG., and surface areas of about 300 sq m/g (when the monohydrate has a crystallite size of about 30 to 40 .ANG.) or 60 to 250 sq m/gram (when the crystallite size of the uncalcined trihydrate is in the range of about 300 to 1000 .ANG.). After calcination of the trihydrate the crystallite size is predominantly in the range of about 35 to 65 .ANG. and the surface area is in the range of about 350 to 500 or more sq m/gram. Average crystallite size of the trihydrate phase determined dry before calcination and the pore size distribution after calcination may be an indication of base structure accessibility related to catalyst activity and stability.
U.S. Pat. No. 3,206,525 teaches a process for isomerizing paraffinic hydrocarbons and recites that the preferred catalyst base material is an activated or gamma alumina as described in U.S. Pat. No. 2,838,444.
U.S. Pat. No. 3,963,601 teaches hydrocracking using a catalyst comprising an alumina-silica support, a Group VIII and Group VIB metallic component and fluorine. A catalyst useful in this process would have a surface area of about 50 to about 700 sq m/gram, a pore diameter of about 20 to 300 .ANG., a pore volume of about 0.10 to about 0.80 ml/g, and an apparent bulk density in the range 0.10 to 0.30 gm/cc.
GP 1,493,928 teaches a process for producing lube oils of high VI by the catalytic hydrocracking of a mixture of heavy hydrocarbons. Suitable catalyst contain one or more Gp VI-B, VII-B or VIII metals deposited in a refractory metal oxide. Promoters such as fluorine, bromine or phosphorus can also be used. If the pore volume quotient of the xerogel is less than 0.5, the catalyst is prepared by incorporation of the metals and at least part of the fluorine into the alumina hydrogel and drying and calcining the composition, provided that the fluorine is incorporated into the alumina hydrogel in sufficient quantity that from the fluorine containing alumina hydrogel a perogel with a pore volume quotient of at least 0.5 can be obtained by drying at 120.degree. C. and calcining at 550.degree. C. Catalyst surface area is not mentioned.
U.S. Pat. No. 3,794,580 teaches a hydrocracking process using a catalyst comprising a Group VI-B, VII-B and VIII metal deposited on a refractory metal oxide support, preferably promoted with a halogen or phosphorus. The process is then run in the presence of added ammonia or other nitrogen containing compound which is converted into ammonia under operating conditions. The alumina has a compacted bulk density of 0.75 to 1.6 g/ml and a pore volume of 0.15 to 0.5 ml/gm.
U.S. Pat. No. 3,709,817 describes a process for the selective hydrocracking and isomerization of paraffin hydrocarbons using added water as a hydrocracking moderator. The catalyst comprises a Group VII-B or VIII metal on fluorided alumina. The alumina has a surface area of from 50 to 800 sq m/gram as determined by the BET method. Preferably the alumina is eta or gamma alumina having a surface area of 50 to 400 sq m/gram (see also U.S. Pat. No. 3,717,586).
U.S. Pat. No. 4,588,701 teaches a catalytic cracking catalyst comprising a mixture of zeolite and an inorganic refractory metal oxide combined with a fluoro salt, ammonium exchanging the product to produce a catalyst having less than 0.3 wt % Na.sub.2 O and optionally adding an effective amount of cation selected from the rare earths. In describing the inorganic refractory metal oxide component of this mixture, the oxide is identified as being preferably alumina and having a surface area, as measured by the BET method of greater than 20 m.sup.2 /g more preferably about 100 to 300 m.sup.2 /gram and having a pore volume greater than 0.35 cc/gram.
U.S. Pat. No. 3,692,697 describes a fluorided metal-alumina catalyst useful for isomerization. The catalyst comprises alumina having associated with it a hydrogenating metal component selected from the group consisting of Group VII-B and VIII and about 0.5 to 15 wt % fluorine. The alumina is described as having a surface area of 50 to 800 m.sup.2 /gram as determined by the BET method. No mention is made of pore volume.
U.S. Pat. No. 3,268,439 teaches a paraffin isomerization process which uses a catalyst comprising a platinum group metal on alumina and at least 1 wt % fluorine, the fluorine being present in an amount of from 1.2.times.10.sup.-4 to 3.4.times.10.sup.-4 grams/sq meter. The alumina used is one of high surface area, a surface area of at least 300 sq m/gram, preferably at least 400 sq m/gram as determined by the BET method being desirable. Again, there appears to be no mention of pore volume.
U.S. Pat. No. 3,121,696 teaches a method for preparing a hydrocarbon conversion catalyst. The catalyst comprises a Group VIII metal on alumina containing combined fluorine. The alumina is a high surface material having a surface area of at least 50 m.sup.2 /gm but higher surface areas of about 100 to about 300 sq m.sup.2 /gram are preferred. It appears that porosity is not discussed.
U.S. Pat. No. 3,830,723 teaches a process for preparing high VI lube oil by Hydrocracking a wax. The process uses a fluorided alumina catalyst containing mixed metal sulfides of nickel and/or cobalt and in addition molybdenum and/or tungsten. In Example 1 Catalyst A had a pore volume of 0.44 ml/g and a specific surface area of 117.1 m.sup.2 /g. Catalyst B had a pore volume of 0.23 ml/g and a specific surface area of 63 m.sup.2 /g. Catalyst E, F and G are reportedly made using an alumina xerogel with a compacted bulk density between 0.75 and 1.6 g/ml and a pore volume between 0.15 and 0.5 ml/g.
U.S. Pat. No. 3,486,993 teaches the catalytic production of low pour point lubricating oils. The process is improved if the aromatics content of the feed is reduced via hydrogenation prior to the isomerization step. The hydrogenation catalyst comprises Group VIII metal on alumina. The alumina is described as loading high porosity and surface area to the composite.